Audio Systems: Merc E-class, volt ohm meter, accessory line

Question
Where would I locate the Acc (the one which starts with ignition) in the merc? Its not on the ISO block and i've looked everywhere? Whats the simplest and easiest way to solve this?


Answer
The accessory line comes off the ignition as you stated.  And it could have a yellow color.  

But, here is the sure way to find it:

Purchase a small vom (volt ohm meter) from walmart or home depot (under $10) and merely find the wiring from the ignition that comes on when the acc position is switched.  Then you know for sure.  

There may be more than one actual wire that comes up 12 volts at acc but anyone of them will turn on the radio or head end unit since very little current is needed because the head has a 12 line directly to the set that provides the big current for the receiver itself.

Hope this helps.C